Design lens

Threat geometry

The shape, size, and movement of danger determine which space remains usable. Compare the visible boundary with collision, level geometry, the camera, and the player’s full body.

ADAPTED FROM GDC 2018

A check from Boss Up

This lens connects to one of the talk’s practical rules.

Design the survivable space

Start with where and how the player can remain alive, then build threats around that response space.

Mechanics

Mechanics that use this lens

Movement & space

Charge

The boss aims, locks its direction, and charges forward. It cannot turn after the lock.

Attack patterns

Arc sweep

The boss anchors one end of an attack and sweeps a dangerous arc across the arena.

Attack patterns

Ground slam

The boss strikes the floor and sends a readable shockwave outward from the impact point.

Attack patterns

Gap volley

The boss fires a broad volley with one readable opening that the player can reach in time.

Projectiles

Projectile fan

The boss releases several projectiles from one origin along committed rays, leaving gaps whose width changes with distance.

Body and melee

Wide swing

A broad melee arc denies the space beside and in front of the boss.

Body and melee

Lunge

The boss commits its body along a short line to close distance.

Body and melee

Grab

A grab replaces ordinary damage with capture.

Body and melee

Burrow and emerge

The boss leaves direct interaction.

Projectiles

Ring volley

Projectiles expand from the boss in every direction.

Projectiles

Spiral barrage

A rotating emitter releases a stream that traces a spiral.

Projectiles

Ricochet projectile

A projectile changes direction after contacting arena boundaries.

Beams

Straight beam

The boss projects a sustained line of danger that controls a corridor and separates warning.

Beams

Scanning beam

A sustained beam sweeps across space from one side to another.

Beams

Rotating beams

Two or more beam arms rotate around a source.

Zones and traps

Marked-area strike

The boss marks a region first and damages it after a delay.

Zones and traps

Shockwave

An impact creates a threat that travels across a surface.

Zones and traps

Lingering hazard

An attack leaves danger active after the initial hit.

Zones and traps

Hazard trail

Movement leaves a temporary dangerous path behind the boss or player.

Arena

Platform destruction

The boss removes or disables pieces of traversable space.

Arena

Shrinking safe area

Danger advances inward or outward to reduce usable space.

Arena

Knockback

A hit displaces the player.

Body and melee

Landing jump

The boss leaps to a committed destination and turns the landing radius into a short radial threat.

Projectiles

Single shot

The boss releases one discrete projectile along a locked line.

Projectiles

Crossfire

Two independent sources fire through the arena so their projectile paths intersect.

Projectiles

Splitting projectile

One projectile reaches a readable trigger, disappears, and releases several committed fragments.

Projectiles

Returning projectile

A projectile travels away from its owner, turns at a readable point, and creates a second dangerous pass on the way back.

Projectiles

Orbiting projectiles

Projectiles remain attached to one center and rotate as a spaced moving perimeter.

Beams

Pulse beam

A fixed beam lane switches between dangerous pulses and safe pauses on a readable cadence.

Area control

Chain explosions

A pre-announced row of blast zones detonates in order, turning each cleared zone into the next safe foothold.

Zones and traps

Mine

The boss places an object that becomes dangerous only after arming and keeps one fixed trigger radius until it disarms.

Arena

Moving hazard

A persistent dangerous area travels through the arena, making the player plan against its future footprint rather than its starting position.

Arena

Converging threats

Separate threats approach one another, narrowing a previously safe region and asking the player to leave it before the overlap.

Arena

Pull

An announced inward force changes the player's movement and can draw their body into a dangerous center.

Additional targets

Turret deployment

A boss installs a fixed weapon whose firing lane remains dangerous after the deployment animation ends.

Additional targets

Threat generator

A boss creates a source that repeatedly emits independent threats until its cycle ends or the source is removed.

Targeting and rhythm

Predictive aiming

The boss samples the player's movement and aims at an estimated future position, creating a readable invitation to change course.

Targeting and rhythm

Source tracking

A visible firing source follows the player's current position during the tell, then commits to a fixed lane.

Targeting and rhythm

Burst fire

A short burst repeats a projectile threat at a readable cadence instead of releasing every shot at once.

Targeting and rhythm

Volley

The boss marks three parallel lanes, commits them, and launches three projectiles together; the player leaves the formation at its edge.

Targeting and rhythm

Delayed activation

The boss plants a harmless rune under the player, fixes its place, then activates it after a visible countdown; the player walks fully outside the circle.

Targeting and rhythm

Speed change

The boss marks one straight crossing, travels its first segment slowly, then visibly accelerates on the same line while the player walks outside the lane.

Targeting and rhythm

Limited spread

The boss announces a narrow cone, then sends three separately aimed projectiles through different angles within its fixed edges.

Structure and readability

Active phase

The active phase is the bounded interval in which an attack's collision can produce its gameplay effect.

Space, movement, and perception

Teleport

A teleport removes the boss from one position and restores it at another without dangerous travel between the two points.

Space, movement, and perception

Boundary attack

A boundary attack begins outside the ordinary playable space and enters through a wall, doorway, arena edge, or camera edge.

Space, movement, and perception

Nested / relocated arena

A relocated arena transfers the active boss fight into another playable space without ending or silently rebuilding the encounter.

Space, movement, and perception

Control mode shift

A control mode shift replaces the player's current movement or response grammar with another one during the same encounter.

Space, movement, and perception

Boss as terrain

The player traverses the boss's body, and access to the damage point depends on a readable route and reliable holding rules.

Space, movement, and perception

Cover and line of sight

A physical object creates safety by blocking the line between a directional threat and the player.

Space, movement, and perception

Forced inertia

A surface or effect carries the player past ordinary input release and turns stopping distance into the central positioning rule.

Space, movement, and perception

Wraparound projectile

A projectile exits one linked boundary and re-enters from another while preserving its direction, speed, and remaining lifetime.

Space, movement, and perception

Invisibility

The boss hides its primary body signal while bounded environmental, audio, or particle traces preserve position and attack intent.

Learn more

Learn more

Found an inaccuracy or have a suggestion for this page? Propose an edit on GitHub